Conventionally, a microscope system including a laser light source capable of switching an output wavelength includes a microscope system having a function of automatically correcting a shift in an optical axis of a laser beam occurring with switching of the wavelength of the laser beam has been known (see, e.g., PTL 1). In PTL 1, a position sensor detects a position of the laser beam to be incident on a laser microscope via a mirror from a laser light source, and the mirror is translated and rotated so that the position of the laser beam detected by the position sensor becomes a predetermined position, to correct the optical axis of the laser beam.
On the other hand, a microscope system that shares an expensive laser light source among a plurality of laser microscopes has been known (see, e.g., PTL 2). In PTL 2, an optical fiber connects the plurality of laser microscopes in parallel with one another to the single laser light source, to enable a laser beam to be output from the laser light source to be simultaneously supplied to the plurality of laser microscopes.
In the microscope system described in PTL 2, all the laser microscopes always remain optically connected to the laser light source. Therefore, an amount of the laser beam to be supplied to each of the laser microscopes is equally divided. A supply destination of the laser beam can be preferably changed depending on statuses of use of the plurality of laser microscopes.
Therefore, an optical member for controlling an optical path of the laser beam, for example, a beam splitter can be replaceably provided on an output optical axis of the laser light source. The laser beam can be selectively supplied to the desired laser microscope by selecting an optical member having an appropriate reflection/transmission characteristic to arrange the selected optical member on the output optical axis of the laser light source. Such switching of the optical path of the laser beam by replacement of the optical member is accompanied by a shift in the optical axis of the laser beam.
Furthermore, in the microscope system described in PTL 2, when the optical member such as the beam splitter is switched, the amount of the laser beam to be incident on a position sensor greatly changes depending on the reflection/transmission characteristic of the optical member. The position sensor can accurately detect the position of the laser beam when the signal level of the laser beam incident on the position sensor falls within the appropriate range.